Process of precipitating metals from solutions containing same.



Patented N ov.25, I902.

s. T. MUFFLY.

PROCESS OF PRECIPITATING METALS FROM SOLUTIONS CONTAINING SAME.

Applibation filed Jam 22. I902.)

'iilllllllllllllllllllllllllmllilllllllllllllllllllllll i I I THE "camsPETLRS ca. mafia-Lama. WASHINGYON. o c.

ATTORNEYS SIDNEY THEODORE lVlUFFLY, OF BOWDRE, GEORGIA, ASSIGNOR OF ONE-HALF TO RUNYON PYATT, OF NEW YORK, N. Y.

SPECIFICATION forming part of Letters Patent No. 714,599, dated November25, 1902. Application filed January 22, 1902. Serial No. 90,751. (Nospecimens.)

To all whom it incl/y concern:

Be it known that I,SIDNE Y THEODORE MUF- FLY, a citizen of the UnitedStates, residing at Bowdre, in the county of Hall and State of Georgia,have invented certain new and useful Improvements in Processes ofPrecipitating Metals from Solutions Containing the Same, of which thefollowingis afull and complete specification, such as will enable thoseskilled in the art to which it appertains to make and use the same.

The object of this invention is to provide an improved process forprecipitating metals from solutions of alkaline cyanids, bromids,chlorids', and hyposulfites, or, more particularly speaking, forprecipitating gold and silver from solutions of cyanid of potassium bywhich said metals have been dissolved out of ores and the like.

The invention involves the use of an apparatus which is fully shown anddescribed herein and which is made the subject of a separate applicationfiled of equal date herewith, Serial No. 90,750, and in the drawingsforming part of this specification, in which the separate parts of myapparatus are designated by suitable reference characters in each oftheviews, Figure 1 is a sectional side view of the complete apparatus whichI employ; Fig. 2, a plan view of abox or case forming part of saidapparatus, a number of which are employed Fig. 3, a section on the line3 3 of Fig. 2, and Fig 4 a section on the line 4 4 of Fig. 2.

In constructing an apparatus for carrying out or putting in practice theinvention which forms the basis of this application I employ a pluralityof boxes or cases A, B, C, D, and E, five of which are shown, but anydesired number of which are employed, and said boxes or cases are all ofthe same shape and are open at the top and preferably square at the top,

the fronts and backs being vertical and the sides inclined toward thebase.

In Fig. 1 of the drawings abox or case A is shown with the side thereofadjacent to the observer removed, and for the purposes of thisdescription I have selected this box or case as a basis, all the othersbeiugof the same form and construction.

The box or case A has two compartments a and b and a transversepartition 0, which does not extend entirely to the bottom of said box orcase, whereby an open space or way (1 is formed at the bottom of saidpartition and by means of which the compartments (1 and b are incommunication.

In the compartment 1) and adjacent to the partition 0 is placed avertically-arranged anode-plate e,of iron, platinum, or other suitablemetal, which is connected by a circuitwire a: with a battery-cell 'y orother source of electricity, and placed in the side of the compartment bis amattress-cathode f, consisting of a cellular porous carbon plate g,placed between two cellular porous carbon casings h and h between whichis placed-a packing t', of filiform lead and zinc composition, saidcomposition consisting of an alloy of twenty parts of lead to eightyparts of zinc or such other proportions as will best turn to a finefibrous condition.

The carbon casings h and h2 are provided in the top and bottom portionsthereof with recesses j and 7' and the sides and ends thereof areperforated, as shown at 76 and k The carbon cathode-plate g and thecarbon casings h and 71 with the filiform packing a, are inclosed in acover g of cotton cloth or other suitable fabric, and these parts formthe mattress-cathode f, with which is connected a leading-wire 00 whichis also connected with the battery '3 or other source of electricitywith which the first-named wire in is connected. The said cathode-plateg' and cathode-casin gs h and 71 are composed of car bon derived fromdestructive distillation of tar, resin, oil, or other suitable powderedcarbon product containing the smallest per cent. of ash and mixed with asuitable cementing compound to be molded in and retain the form shownand described.

Between the anode e andthe mattress-cathode f is a space inclosed byframes Z and Z said frames being composed of glass, porcelain, or othersuitable substance that is a non-conductor of electricity, and betweenthese frames is preferably placed ascreen Z composed of any suitablefabric.

It will be observed that each of the boxes or cases A, B, O, D, and'E isprovided with one of the batteries y, and the corresponding parts ofeach of these boxes or cases are connected with the correspondingbattery, as hereinbefore described, and as shown in Fig. 1, and saidbatteries are provided with a suitable support if, which may be locatedat any desired point. I also provide an airpipe m, which is providedwith a plurality of branches m equal in number to the boxes or cases A,B, G, D, and E, and referring to the box or case A, one of these branchpipes m extends downwardly through the compartment a, and is connectedwith a perforated cross-pipe 11., located in the bottom of thecompartment b beneath the mattress-cathode f, and these pipes areintended to supply air under pressure to the space beneath the saidcathode, as hereinafter described.

It will be observed that the boxes or cases B, O, D, and E are arrangedin a hori zontal line, and each of said boxes or cases is slightly lowerthan the one to the left thereof, and each is'provided at the frontthereofthe term front being applied to the righthand side or end of saidboxes or caseswith an overflow 0, whereby the contents of each of saidboxes or cases may be discharged into the adjoining box or case at thefront or right-hand side thereof, and said boxes or cases may beinterchanged, as hereinafter described, whenever desired.

The upper edge portion of the partition 0 is recessed, as shown at 0 toprevent the overflow of the solution at the outer sides of the box orcase, and the anode e and mattresscathodef may be arranged as describedand multiplied in each box or'case. The object of the fabric screen Zbetween the frames Z and Z is to arrest any slime or other objectionablesubstance from imperfectly-filtered solutions, also precipitated baseelements or anions detached from the anode e.

The pipe m is in practice connected with a blast-engine to supply airunder pressure, whichmay be either hot or cold, as desired, and in orderto create the most effective temperature.

The operation is as follows: A solution of cyanid of potassium or othersuitable solution containing gold and silver in a solvent state isplaced in a storage-tank 2 and fiows therefrom through a pipe 3,provided with a controlling-valve 4, into the compartment a of the boxor case A and passing under the partition 0 rises through themattress-oath ode fand flows over the apron 0 into the next box or caseB, and said solution passes in the same manner through the boxes orcases B, C, D, and E and flows from the last of said boxes or cases intoa tank 5, where it is strengthened to a proper standard by the additionof fresh cyanid of potassium for further use in leaching ore. Theelectric currents for the purpose of electrolytic decomposition andprecipitation are supplied through the leading-wires a: and m from thebatteries y, which are sufiicient in number and strength to produce therequisite electromotive force to accomplish the best result in theshortest time-that is, the most perfect electrolysis or rapidprecipitation of gold andtsilver from solution. By means of theelectrolytic field confined .in the insulating-frames land Z which areplaced between the anode e and the mattress-cathode f, I provide for thefree circulation of the compressed air through the solution and for thefree penetration thereby through the mattress-cathode f, and thus supplyan abundant amount of oxygen to enable the molecules of the solution tomore rapidly exchange their atoms. In the cellular porous form of thecarbon plate 9 and carbon casings 7t and h I provide relatively numerouselectrolytic circuits in which the electric currents can be greatlymultiplied. For instance, while a large or strong electric current, asin other apparatus, may pass'through the electrodes and electrolyticsolution in a constant direction my apparatus has the additionaladvantage of many small electrolytic circuits being locally maintainedwithin the mattress-cathode by chemical reaction on the filiform packingi and also continuously increasing the electrolytic conduction bydepositing gold and silver cations in the many cells in the carbon plate9 and carbon casings h and k thus keeping the electrolytic action moreconstant than with the use of ordinary exposed cathodes, where corrosionby salts of base metals and slimes of imperfectly-filtered solutionscover the surfaces of cathodes and affect the state of the electrolyticbalance. From time to time, as required, a supply of the partly-solublefiliform alloy packing t is added to the compound cathodef through therecesses j and 9' to replace the portion which has gone into solution ormolecular exchange for the gold and silver atoms precipitated within thecathode f. Through the parts 9, h, if, and 't', constituting cathodef,and fabric covering 9 the solution filters and circulates in theinclosed electrolytic field within the insulating-frames-Z and Z betweenthe ironplate anode e and the compound cathodef, and thefabricfilter-screen Z between the insulating-framesl and Z prevents thepassage of the base elements or detached anions from anode e to cathodef, and thus injure the same by corrosion.

From the foregoing description it will be seen that the cathode which Iemploy is composedof two or more elements or metals separate in theelectromot-ive scale, one of said elements being in the form of a plateor electrode and the others being preferably filiform and intermixed toform a subject to local action and in or among which filiform elementsthe said plate is located. It will also be seen that the boxes or casesA, B, O, D, and E constitute cells, into and through which the solutioncompound is passed, and any desired number of these cells may beemployed, as will be readily understood, and the shape thereof may alsobe varied, all that is necessary in this connection being that the form,construction, and

compound element arrangement of said cells shall be such as to permit ofthe placing therein of the separate the mattress-cathode f, andafter'the elecof the solutions.

trolysis of the solution is finished the carbon plate g and carboncasings 7t and h2 are incinerated, the ashes containing the gold andsilver added to the product of the filiform packing 7;, together withwashings of the mattresscover, and the product is smelted into bullionin the usual way. The box or case A is then refitted with a newmattress-cathode fand placed at the right-hand end of the series, andthe other boxes or cases are moved up and the box or case B, containingsome gold and silver, is the first box or case in the electrolysis ofthe next solution.

In the form of cathode I employ I secure a greater area for thedepositing of metals than can be proportionately obtained in anyapparatus using an ordinary solid plate cathode, and because of thisadvantage Iam able to use a current in one direction of greater electricenergy, and thus secure a greater current density and efficientpotential difierence between the e1ectrodes,thus more readily polarizingthe molecules of the solution and causing them in the quickest possibletime to deposit their non-metallic atoms in contact with the anode andtheir gold and silver atoms in contact with the cathode.

By meansof the partly-soluble filiform packing t'within themattress-cathodefl ob tain increased chemical action that materiallyassists in preserving a constant conduction of the atoms from moleculeto molecule through the electrolytic field until they come in contactwith and are eventually set free at the anode and cathode.

In the use of air-currents of effective temperature I provide abundantoxygen'to exchange more rapidly for the gold and silver atoms in themolecules of the solution, and in limiting the electrolytic fieldbetween the electrodes 6 and fin one compartment b,with independentelectrical connections m and 00 with the battery y or other source ofelectricity, I secure a more perfect polarization By confining theelectrolytic field within the insulating-fram es land Z with the fabricfilter-screen Z between them I prevent floating non-metallicprecipitates at the anode e from passing through and corroding thecathode f, which results in a purer gold and silver product and moreeffective chemical action. In this method as a whole I secure a perfectand constant polarization of the compound molecules of the solution anda more rapid and complete deposition of the gold and silver atoms at thecathode.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is

1. The herein described electrochemical process for precipitating goldor other metals from solutions, consisting in obtaining secondary orincreased electrochemical action by passing a solution of requisitetemperature combined with warm air to supply oxygen into and through afiliform and partly-soluble composition of lead and zinc inclosed in aporous cellular casing of carbon, together with a suitable plate-anodeand comprising electrodes having connection with a source ofelectricity, substantially as shown and described.

2. The herein described electrochemical process for precipitating goldor other metals from a solution, which consists in passing the solutionat a-requisite temperature into an electrolytic field between electrodesin combination with a warm-air current, and preventing the floatingtherefrom of corroding non-metal precipitates through the solution,substantially as shown and described.

3. The herein described electrochemical process for precipitating goldor other metals from solutions, which consists in passing a solution ata requisite temperature in connection with warm-air currents into aninsulated inclosed electrolytic field between electrodes, with means toprevent the floating therefrom of corroding non-metal precipitates thepassing of the said solutions and air through a filiform and partly-soluble composition of lead and zinc inclosed in a porous cellular casing ofcarbon connected with a source of electricity, substantially as shownand described.

4. The herein described electrochemical process for precipitating metalsfrom solutions which consists in passing the solution in connection withwarm-air currents into an insulated inclosed electrolytic field betweenelectrodes, and preventing the floating therefrom of corrodin gnon-metal precipitates, and the passing of said solution and air througha filiform partly-soluble composition of lead and zinc inclosed in aporous cellular casing of carbon, and adding to such solution freecyanid of potassium, substantially as shown and described.

In testimony that I claim the foregoing as my invention I have signed myname, in presence of the subscribing witnesses, this 17th day ofJanuary, 1902.

SIDNEY THEODORE MUFFLY.

Witnesses:

PATRICK NEWTON PARKER, ANDERSON GLENN DORSEY.

